Modern gas turbines particularly aircraft engines must satisfy the highest demands regarding reliability, weight, power output, efficiency and their life duration. During the last decades aircraft engines have been developed particularly in the civil sector, which engines fully satisfy the above demands. These aircraft engines have reached a high degree of technical perfection. In the design of aircraft engines the selection of the materials plays, among other things, a critical role. This applies also to the search for new suitable materials.
The most important materials that are used these days for aircraft engines or other gas turbines are titanium alloys, nickel alloys, also referred to as super alloys, and high strength steels. The high strength steels are used particularly for shaft components, gear components, and for compressor housings and turbine housings. Titanium alloys are typical alloys for compressor components while nickel alloys are suitable for the hot components of the aircraft engine.
A very promising group of a new material for future generations of aircraft engines are so-called fiber reinforced composite materials. Modern composite materials comprise a matrix material which may be made of a polymer, a metal, or ceramic matrix and fibers embedded into the matrix material.
The present invention relates to a composite material in which the matrix is made as a metal matrix. Such a material is referred to as a metal matrix composite material, in short MMC. In connection with high strength MMC materials in which titanium is used as matrix material, the weight of the structural components can be reduced up to 50% compared to conventional titanium alloys. Fibers of high strength and a high modulus of elasticity are used as reinforcements.
Such fiber reinforced composite materials are known in the prior art. Thus, European Patent Publication EP 0 490 629 B1 discloses a pre-shaped blank for a composite material including a foil whereby the foil comprises a groove and a thread shaped reinforcement arranged in the groove, and wherein the pre-shaped blank has the shape of a ring or of a disc. For the production of a multi-ply composite structure one proceeds according to European Patent Publication EP 0 490 629 B1 in such a way that several such pre-shaped blanks are stacked whereby the pre-shaped blanks are consolidated under the influence of heat and pressure to form a fully dense composite material. Further composite materials and methods for their production are known from European Patent Publication EP 0 909 826 B1, from U.S. Pat. No. 4,697,324 and from U.S. Pat. No. 4,900,599.